Scarlet-rumped Tanager
Ramphocelus passerinii
The adult Scarlet-rumped tanager is 16 cm long and weighs 31 g. The adult male is mainly black except for a scarlet rump, silvery bill and dark red iris. The female has a grey head, olive upperparts becoming brighter and paler on the rump, brownish wings and tail and ochre underparts. The female's plumage is the one that differs most from Cherrie's tanager. Immatures have an orange tint to the underparts and rump, and look like a paler and duller female Cherrie's tanager. The Passerini's tanager's call is a sharp wac.
ID text from Wikipedia, CC BY-SA 4.0
Yellow-faced Grassquit
Tiaris olivaceus
It is a small bird with a conical bill, sharper than that of the related seedeaters. It is 10–10.7 cm (3.9–4.2 in) long and weighs about 8–10 g (0.28–0.35 oz), depending on subspecies. The adult male has an olive-green back, and its face and breast are black apart from a bright yellow throat, supercilia, and lower eyelid spot. The rest of the underparts are greyish olive. The beak and eyes are dark, while the legs are grey. The adult female is slightly smaller on average than the male. It is dull olive-green above and paler grey below, and may have some dark breast smudges. Voice: The yellow-faced grassquit has a weak buzzing trilled ttttt-tee call. The song is a varying series of high thin rapid trills. Given for a prolonged time, it is melodious, yet subdued, and often only heard from a short distance away.
ID text from Wikipedia, CC BY-SA 4.0
Where you might meet both
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